There exist today many tools for a motor vehicle owner that are use to provide assistance in a variety of difficult situations. The most common of these tools--a lifting jack--is used to lift a motor vehicle's tire off the ground in order to change such tire when it goes flat. Such jacks are indeed considered standard equipment for any motor vehicle, and are invariably provided by vehicle manufacturers with the purchase of a motor vehicle.
While it is certainly annoying and trying to have to change one's tire when it becomes flat, getting stuck in ice, mud or snow can be equally difficult. Indeed, in cold-weather climates, having one's vehicle immobilized in ice or snow occurs just as frequently, if not more frequently, than having a tire go flat. It would be desirable, therefore, if drivers had available to them, a tool that could be used to enable such tire to grip the ice or snow for ready extraction of the vehicle, which is as ubiquitous and easy-to-use as an ordinary vehicle jack. Without such a readily available tool, it is necessary for the driver of the immobilized vehicle to call a tow truck or similar vehicle and then wait for assistance.
Vehicle theft is also a serious problem for vehicle owners. Various alarms and security systems, as well as so-called "tire boots" have been devised to prevent theft. But security systems are expensive, and carrying around an extra boot device is cumbersome and consumes precious vehicle cargo space.
The prior art includes many jack-type lifting devices, such as the standard ratchet-bar jack that lifts the vehicle straight up for tire removal, and the pantograph-type jack such as is shown in U.S. Pat. No. 4,092,012. But, these jacks are generally limited to a single purpose, namely lifting, when in fact their ratchet mechanisms could be adapted to other purposes as well.
U.S. Pat. No. 3,991,977 shows an interesting adaptation of a standard ratchet-bar jack to help extract a vehicle when such vehicle is stuck. In its ordinary application, the ratchet bar pushes apart, providing upward force to lift a vehicle. In its extraction application, the ratchet bar pulls together. When one end of the ratchet bar is attached via a chain or similar device to a stake in the ground or other immobile object, and the other end is attached via a chain or similar device to the vehicle, the pulling together of the jack serves to help extract the vehicle from its stuck situation. However, the device in this patent is difficult to use, in that one must have an immobile object nearby for chain attachment, or must have available a stake as well as a sledge-type hammer to drive the stake into the ground. Further, this invention requires the user to iteratively hook and unhook the chains using a pin mechanism as the jack contracts, and iteratively reexpand and recontract the jack. This is quite cumbersome. One would expect that the time required to set up and use this device, particularly in cold, blustery weather, is substantial. What is meritorious about this device, is that both the lifting (jack) and the extraction functions are achieved by a single, dual-function device, and that the jack bar that one already has in the vehicle, is used to serve a second purpose.
The prior art does disclose other devices that are specifically, solely, designed to stop skidding of tire wheels, and thus help extract a vehicle that is stuck in ice or snow. Yet, there are a number of defects common to all of these. For example, U.S. Pat. Nos. 4,036,273, 4,228,838, 4,960,159, 4,960,160, and 5,033,522, are essentially chain replacement devices. All of these involve complicated hardware, and are designed for more permanent tire use. They most certainly cannot be easily mounted into the tires in perhaps 20 or 30 seconds, or removed in a few seconds once extraction is completed. Further, the hardware attachments themselves are quite complicated. As these devices are used in adverse (e.g., wet, icy, muddy) road conditions, it seems that with all the springs, pulleys, wires, etc., used by these devices, the opportunity for mud, sand, ice, salt, etc., to get stuck in, and ruin these devices, is quite high.
U.S. Pat. No. 5,156,695 requires that an adapter plate be mounted to the vehicle wheel, which is cumbersome and does not lend itself to a 20 to 30-second attachment that would be desirable during an immobilization emergency. The device in U.S. Pat. No. 5,540,267 must similarly be secured to the wheel. U.S. Pat. No. 5,454,412 requires the wheels to have holes in them (hub caps off), and requires the installer to bend down behind the back side of the tire to pull these devices through. This must be done as many times as there are strips being installed, so, for example, if four strips were being installed, this procedure would be performed four times over in sequence. Similarly, U.S. Pat. No. 4,116,254 is useful only for wheels with holes in them, which eliminates its applicability for many vehicles. U.S. Pat. No. 4,386,643 is also very cumbersome to use, requiring a great deal of preadjustment before use. U.S. Pat. No. 4,209,049 also involves a great deal more hardware than is desirable (see, e.g., FIG. 4 therein), and is thus cumbersome to use. U.S. Pat. No. 4,176,704 also appears more cumbersome than is necessary.
Also, none of the above-reference patents disclose how they can be used for tires of varying tread width, and are limited to a single tread width of tire. A vehicle owner with two different vehicles having two different tire tread widths would need to purchase two different such devices.
U.S. Pat. Nos. 4,122,881 and 4,872,496 utilize less extraneous hardware than the other devices cited above, but still require a fair amount of time and work to be mounted on a tire. U.S. Pat. No. 4,192,367 appears to be the simplest of all the devices disclosed in the prior art, but the grip surface can clearly be improved, and it would be desirable for this device to adjust to different tread widths. It would also be desirable if the user could gain more control over the positioning (spacing) of the grip surface around the circumference of the tire. Also, this device, like all the others discussed above (except U.S. Pat. No. 3,991,977), is confined solely to a single purpose, namely, vehicle extraction. It would be desirable, so long as one is already carrying around vehicle safety hardware, to have that hardware be useful for several commonly-needed functions.
The prior art, e.g., U.S. Pat. Nos. 4,651,849, 4,833,442 and 4,854,144 also discloses various "tire boot" anti-theft devices. Yet the process of mounting many of these is rather cumbersome, and these too, are confined to a single purpose, namely, vehicle immobilization to prevent theft.
It would be desirable if a single, multipurpose device were available which can be easily adapted to perform several functions, namely: lifting a vehicle so that a tire can be changed (i.e., vehicle jack); extracting a vehicle from ice, mud, snow, etc.; immobilizing a vehicle against theft (i.e., vehicle boot); and even locking the inside steering wheel so that it cannot be turned, which is also prevents theft. Such a device should be simple and easy to use, should be capable of deployment in a very brief time period, and should be compact for easy storage. Such a device could then be used and stored as ubiquitously and conveniently as a conventional jack, but would provide the vehicle user with safety and security for a wider range of vehicle problems. Such a device should be useful for tires of any tread width.